1. Field of the Invention
This invention relates to the controlled release irrigation of potted plants and, in particular, to a controlled release hydraulic watering apparatus for insertion into the soil in a conventional individual plant pot or for mounting a controlled release water reservoir on a nursery or home plant pot support tray for individually potted plants, the tray having a capillary sheet for irrigation in the tray bed.
2. Description of the Prior Art
It is well known that plant growth and health is dependent upon carbon dioxide, nutrients, and, most importantly, a proper amount of water. To reach and gather water and nutrients, each individual plant employs an intricate network of roots for obtaining the proper amount of moisture within the surrounding plant soil. Potted plants present a problem in that the root structure is confined within the plant pot, making the survival of each plant dependent upon the moisture directly made available within the confines of the plant pot or its surrounding environment. Typically, if a plant gets an over-abundance of water, the plant may drown, even in an irrigated system, in that plants often over-compensate if too much water is available by trying to store water for dry periods, resulting in a drowning of the plant. Obviously, if the soil lacks sufficient water, the plant will ultimately not survive.
The applicant herein has developed numerous devices as shown in the prior art that basically provide for continual irrigation, especially of individually potted plants. Disclosed in my U.S. Pat. Nos. 3,220,144 and 3,193,970 are devices for controlling and regulating water to a single plant. My U.S. Pat. No. 3,778,928 teaches an irrigation system for controlling irrigation to a plurality of plants in individual containers. In my U.S. Pat. No. 4,245,434, I disclose a further improvement in a system for the irrigation of soil in plant containers characterized by the use of a capillary sheet having a plurality of evenly spaced perforations with a layer of silica sand acting as capillaries, as described in the capillary sheet used in U.S. Pat. No. 4,001,968. The objective in these devices is to provide proper irrigation to plants.
In the present invention, I have found that a reservoir for water can be employed that is constructed of a terra cotta or similar clay material having a comparable permeability and can be used for metering out through the terra cotta wall a controlled release of the proper amount of water to be used by a plant, either in an individual potted plant or with multiple individual potted plants that are mounted on a tray that uses a capillary sheet or plastic strips in conjunction with horticultural matting. Thus, the invention disclosed herein has two different modes of operation.
In its simplest form, the present invention uses a terra cotta water reservoir that is shaped like an inverted truncated cone with an open top and closed base that holds water, the reservoir being mounted within, or a large portion within, existing soil in even a larger plant pot to provide controlled release of water placed in the terra cotta reservoir. Applicant has found that the use of terra cotta or perhaps a comparable permeable clay provides a proper amount of permeation of the water from inside the terra cotta container reservoir that permeates through the terra cotta wall into the surrounding environment at a desirable rate, offering sufficient moisture and water to the plant or surrounding plant tray without over-watering for proper health of the plant. Another advantage is that with open top reservoirs, a visual inspection of the amount of water in the reservoir is easily and quickly accomplished. Finally, the controlled release system using the terra cotta reservoirs is also inexpensive in that terra cotta plant pots are currently being manufactured in large scale and all that needs to be done is to have the bottom hole plugged for the reservoir to function in accordance with the entire system in the present invention.